I am a little unclear on what you mean.
You can set the items on the right hand side to have menus which expand when clicked on. This can be done from the configure page in Start8 config - change from Display as a link to display as a menu.
But the all programs link on the left will always be a scrolling treeview and this is also the case in Windows 7. Windows XP was the last OS to have an expanding menu for all programs.
